Do I risk trying for a different job with my employer while on maternity leave?

[ThoseBigKnickersAreMine]

I'm due to go back in the spring. I was working 4 days/week and have successfully applied for flexible working, with 2.5 days/week approved for my return. So far so good.

I have an at times rewarding charity job, but it is highly specialised and dead-end - there's nowhere to progress to and, should I lose my job/want to move on, similar posts are like hens' teeth outside London (I'm in the sticks). So I'd been thinking of treading water for a while and, once DD is 3 or 4, looking into a career shift, more hours, possible move into management, etc.

My new manager has told me however that my most rewarding, substantial and CV-impressive work will go to others in the team who are full-time (even though I managed this work fine part-time in the past ) and I'll be handling smaller relationships and working with a different focus (which I don't enjoy as much) when I get back. Since this chat, I've felt really demotivated, and as though I'm actually going to be going backwards with work, not even just plateauing.

Last week, I spotted a job on the organisation's website for a post I really quite fancy. It's in a completely different department, different discipline altogether, but I have a lot of transferable skills relevant to it, have worked closely with this team in the past and enjoyed it, and it's more relevant to my degree. I'd never planned to go this route (but didn't know exactly what else I'd do either), yet am wondering if I should give it a go. It's a level above my current role with project management responsibilities, and it's full-time.

Would I be foolish to have an informal chat with the senior manager in this other department, to express my interest? I don't want to formally apply and give my current manager the impression I don't want to return to my present job, thereby jeopardising it (it's reasonably paid and close to home - I kind of need it at this point in DD's life) ... I could end up with neither. (My employer has form for manoeuvring people it doesn't want out.) But at the same time it seems like an opportunity; it's going to be easier (I would imagine) to shift career with an existing employer where you're a known entity. Even if it didn't work out, I'd acquire transferable project management skills, making it easier to move on in a few years. I'd want to stick with part-time, but might have a chance with this, as my employer can struggle to recruit due to being fairly remote.

What do others think? Do I stick with my current role because it's secure, part-time and won't be too stressful while I have a baby? Would moving into even part-time management be too stressful whilst trying to settle my daughter with her childminder? Can you even project-manage part-time?! If it's worth a punt, how do I do it so as not to risk my existing job? A formal application will out me. I was thinking of first having an off-the-record phone call with the senior manager who would manage the role, with whom I've worked before, and possibly suggesting a lunch depending on how it goes.

Good idea or am I not thinking straight (sleep-deprived!)? Grateful for any pointers and/or words of wisdom.

[LoveMILbut]

Go for it! Definitely have an informal chat with senior manager. He/she should be discreet enough not to mention it to your current manager.

[Littlef00t]

I tried project management pt and it didn't work for me. V fast paced and not being in daily, or being able to meet with seniors when they were free because I wasn't working didn't work out. Moved into comms and marketing.