Increasingly reliant on wheelchair

Hi Will,
Welcome to B&W!
I'm sorry to hear that your health is deteriorating.
There are 2 mobility descriptors, the first deals with the logistics of journeys, and how successfully you can complete these. (This considers all manner of journeys - car, bus, train or on foot, and may well use a combination of all.)
Mobility 2 deals with how far you can walk.
In a nutshell, if you are unable to walk more than 200m you will score points.
As with all descriptors, including Daily Living ones, you need to consider 4 'reliability' criteria- all 4 need to be satisfied.
•safety - is there a risk of substantial harm - eg by falling. (You not actually fall often, but when you do you risk hurting yourself.)
•reasonable time - no more than twice that of non disabled person
• repeatedly across the whole day as many times as reasonably required
•acceptable standard

So think about where you might walk. Remember that even if you go by car, there will be a short few steps needed to get from eg your home to the entrance to a shop etc.
How far is this? A friend could help pace out the distance if need be.
Do you have any problems? - falls, limp, balance issues?
Do you get significant pain, out of breath fatigue, dizziness or similar? If so, this means you won't 'walk' to an acceptable standard, so you would fail to achieve this criteria. If the pain etc is present right from the start, then since you can't achieve 'an acceptable standard' your walking ability for PIP will be 0metres. If, for example the pain or breathlessness comes on after 25m then thst would be your walking ability and you should 'tick' descriptor 2c or d, (20-50m) depending on whether you need to use an aid such as a walking stick.
Repetition - particularly if you have a car, it is entirely possible that you would wish to make several journeys a day. Each of these will have a small walking element, as suggested above. For example, taking the kids to school, go to post office, take some money out from the bank, get a pint of milk from the local shop. Go home. Pick up kids etc....none of these journeys would be unreasonable, and perhaps other journeys might also be required throughout a day. Think about what you woukd like to do. Can you actually complete all the walking bits? What stops you if you can't? Maybe it is pain or fatigue, maybe if you do walking one day you are too fatigued,or achy to go out the next day? If you can't do reasonable repetitions you fail to meet the criteria.
Your walking ability under PIP is the distance that allows you to fulfil all the criteria, for the majority of days. A day where you fail one or more of these criteria is a day that counts towards the majority. (A few better days won't preclude points.)
Therefore if you can't be safe, acceptable, reoeat etc your PIP distance could be 0metres even though you are able to move along a greater distance.
Your post states you use a wheelchair. Analyse why you need the chair, and how far can you walk without it. (Using the explanations provided above.) A wheelchair is NOT an aid here, as if you use it, you are not walking at all. The fact that you need this of course will be strong evidence to show that you have very limited walking ability.
Were you prescribed the wheelchair by eg physio or GP ? - if so get a statement to prove this. This will carry more weight than you simply choosing to use a chair.
A similar kind of analysis can be undertaken in respect of all descriptors to identify whether you can fulfil the 'reliability' criteria. (This is Regulation 4(2A).)
I hope this helps.
Good luck with your claim.
Let us know how you get on.
LL26