Welcome, your get alot of good information here and most of the disposable diaper information has been given to you alredy so I dont need to be a parrot. But if you look at my icon youll see that is my “fursona” or identity on a bicycle, im not eligible to drive a vehicle because of vision, so I can put in some great advice for you to return to your love, cycling. I ride between 3000 & 5000 miles a year on various types of bicycles be that my carbon xc bike, gravel, electric, cargo, or road bike, Im not incontient myself but have ridden various distances while diapered, they do say curiosity kills the cat, but i had to do it atleast a few times and can right away say that disposables seem to fall apart under the stress of serious cycling(non upright aero positioning) after about 5-10miles. A decent cloth diaper and lotion is basically the same as a set of roadie lycra shorts that you pee in and can help comfort further than your old underwear with the only downside of being warmer. Now your biggest enemy on the bicycle is moisture control and rashes get a good chammy butter/diaper cream as powder alone wont be enough, you want basically seal off your skin as the repetitive motions and wetness is actually the reasons typically roadies use those shorts not just for padding.
The now this might sound like a joke but maybe you should look into triathlons as it is pretty much normal to pee yourself on purpose during those races, and trust me i see the damage it does to the bikes. Its almost like if your a triathlete that doesnt pee on themselves youd be in the minority. I will say this your mechanic wont like you but as long as your wearing black lycra itd be difficult to tell if you wet yourself and the bike and saddles can handle it just expect more bearing wear in those area directly below the seat. If you think that this is the end of your career it is not and in fact if want to see a unmentioned side of cycling its the peeing while biking as in aero positions itll place pressure on your bladder so having to take a wee isnt fun, depending on the situation in racing say in the tdf if you dont do the mass pee break the rider will try and pee with a buddy holding them or just let it go.
Maybe Ill start my r&d project for the best diaper for bicycling back up, as I have a few comorbities that could lead to incontience if my condition were to ever worsen. Being car-free/bicycle dependent Ive actually put thought into designing a set of cycling shorts that also function as a diaper.
Ill have to reach out but I used to hang out with a ex pro(uci cat 1 in cross and mtb) that was apart of this subculture as well and if shed have any feedback for you.