OP ALL your responses are those of someone in a panic, desperately trying to get away from something that they can't cope with. At no point have you (despite your posts being all about YOUR needs) identified that it's YOU that has an issue with this journey and that you need to do something about it (not arrive at a fantasy solution, for all the wrong reasons, HE).
You freely say that you felt overwhelmed going to school when you were a child. OP there will be a reason/reasons for this and that's where your focus should be, unpicking that. Maybe some significant family upheaval / death in the family / divorce or other major event that resulted in severe anxiety. I sympathise as I have it myself and have since a child. It's bloody tough BUT you have to face it and tackle it, not run away from it.
Yes, of course, it's your choice at the end of the day, but your motivation for it is all wrong (sorry OP but it is).
I agree with others that if you can't cope with the known daily bus journey then you're not going to cope with what will be a much less predictable /familiar set of outings and journeys not to the same place every day, but to a variety of places, new places, places you've never had to get to before which you already know you'll have to use public transport for because you don't drive (and frankly, thinking that your DH could take time off work to ferry children around for this is absolutely bonkers, or that you could fit all the trips stuff in at the weekends!).
You've said a couple of times about the 'getting ready' and 'rushing in the morning'. A lot of anxiety management is about being prepared (like a boy scout) and as much as I can't stand the woman Anthea Turner (vom) does have a way with setting yourself up for success on such matters - it's amazing how improved the mornings could be for you OP if you had this super organised I'm in control approach that just repeated every morning. It's things as simple as having bus passes instead of trying to find change that sort of thing as well. So when you say 'there's no other solution' that's not true - there is the organising solution which would remove two of the things you mentioned - feeling overwhelmed and rushing. If you're saying you're rushing every morning it's because you're not organised and there's no getting away from that. If a normal level of morning chaos is too much for you, organise out of the mornings so it just can't happen. The choice and the capability to do that rests with you and IS definitely achievable by you but it sounds like you are a victim of your anxiety at the moment and such that there is literally no forward progress in tackling it even in simple practical ways, things that you could prepare for over Xmas and the New Year and have in place for next term....
And so you don't think I'm talking theoretically, I'm not. As I say I have anxiety and have to plan all my journeys to the nth degree (especially if it's somewhere new and regardless of whether driven or public transport) but when I'm travelling the same journey every day, a journey that never changes essentially (apart from a late train or cancelled train and whether I end up sitting next to the smelly snoring man or not) it's not stressful. It shouldn't be stressful to you OP to do the same journey day in and day out and that's coming from someone who gets what anxiety is like and lives with it day to day. This tends to indicate that ALL of your life unless you are sequestered in the house - 'safe' - gives you this overwhelmed feeling and that's far from normal and needs addressing - by you. But not by picking HE for all the wrong reasons. Your level of panic coming through in your posts and when you describe your mornings is someone running away terrified by the prospect but you need to understand that what you describe is extremely excessive and disproportionate.
As parents the onus is on us to be the best adults we can be - so if your anxiety is affecting your life to this extent and producing a plan which is based completely on wishful thinking and unrealistic 'solutions' (eg hubby taking time off work to do HE trips ) then you need to sort things out and what you need to sort out, is YOU.
WHY does a journey like that feel so overwhelming? WHAT is triggering that feeling? HOW could better in-advance organisation be utilised to reduce the overwhelming feeling? THIS is where you should be applying the effort because I see what others see: not only is your plan unrealistic and predicated on your needs first and foremost, you are already acknowledging (especially with the DH taking time off WORK to do HE trips!!) that you won't be able to cope with HE either! It won't be better OP, I genuinely believe it won't.
You can run from the need to attend to your own issues as much as you like (I get it, it's hard and anxiety takes a toll on you that many people who don't have it, just don't understand), but this is what's at the root of this and I fear you'll be like the example given earlier - you'll be no better off and the kids will end up isolated and receiving both a poor deal educationally as well as socially because you'll simply be replacing one known predictable journey with a whole load of journeys that you have never made before and which may involve all kinds of convoluted public transport journeys way 'worse' than the regular school and back bus journey which you are currently facing. The issue remains the same and unaddressed, your anxiety. I know it's hard, but this is what you need to tackle.
You need to work with a counsellor who can unpick the issues, help you plan your way through a journey looking at all the parts which make you feel overwhelmed and how to tackle each of those steps, finding ways to cope with each concern and how you'd address it, so that you can cope with all the journeys etc. If you look at TED talks there's one about a teen who suddenly got severe anxiety and just started sobbing when he pulled up at the school gates and ended up not being able to go to school for ages. What is clear from this and in dealing with anxiety is that the approach to it is twofold. You have to unpick the feelings and the why's and get help with that, BUT, you also have to expose yourself to the stressful thing or it doesn't get better, it doesn't stay the same, it gets worse, and your world shrinks (and hence your children's) and you never actually tackling the root cause that's led to this idea OP, and that's your anxiety and panic responses to routine happenings. That's not your fault, it's just how it is, but you do need to tackle it and only you can do it. And this needs doing before you start any HE otherwise you - and your kids - are going to be stuck in the house 24/7 unable to go anywhere and surely you don't want that for them?
Don't YOU want to feel better each day, not feel overwhelmed by stuff as well - you deserve to feel better you really do but the way you're thinking of going about it is not a solution, it's a distracting panic idea that I don't believe will bring you the peace that you think it will.