They always say the max waiting time because that way patients aren't more frustrated, and don't contact them earlier. It can be up to 4/5 months normally where I know of more max 4, but if it's earlier, great. It also depends it could be a private diagnostic centre so the NHS outsources, they often have cabins, etc, so they aren’t in a hospital, sometimes dotted outside.
Also, they will tell you biposy results if they were bad, or they'll be on the app, etc. It's likely the letter was dictated and typed before the buposy results came back anyway. Even if I'm wrong it's okay, they'll explain it all, and if you are right then they clearly are unsure and need the MRI to be definitive, so it can still be nothing.
Also that's good it's in 3 weeks, a plus of them telling patients the max, is patients are happier when it's less than expected (even if it's still been quite long for an urgent one) but this distracts from that. They should definitely have enough to make a plan by late November and then get on with it. Definitely ask your consultant and the secretary to put you on the list for anyone, so be on that consultants list but if any other consultant is free, has a cancellation, comes back from leave etc or whatever you could potentially have it earlier. Not sure if everywhere allows this but some places I know do, and it's happened for people I know.
I have found incontinence pads very thick and useful for years, also they have incontinence type pants which you may be taking about. Also period pants are great and get good thick ones, I've heard the Wuka ones are good, and others as well.
Honestly safety and not leeking is sexy as the chronic illness slogan goes, there's no need to feel shame either, I did for this, other symptoms, using a mobility aid, grab rails etc but now I don't care and I shouldn't. Neither should you, it's self care and that's important.
Also when you go back to the hospital, ask them what pads they are, they likely could give you some as well, even when you go for the MRI if you go to the ward inquires desk or the outpatient gyne ward, they should give you some. Our at the very least tell you the brand. Hopefully this is the last hurdle and then you can be booked for surgery and other treatments. How has today and the last few days been symptom wise? I hope your half-term break has been good.