Hi terdun9
Did you keep a copy of the original form, if you did then use it as a template and make any changes necessary such as prescription changes, any new conditions, remember you must have had a new condition for 3 months and expected to last for at least 9 months.
If you have no new support documents, then use your previous support document if it is still relevant.
You normally get a renewal form up to a year before your claim runs out, before covid it was 6 months but there has been a bit of a backlog.
Gary
Nothing on this board constitutes legal advice - always consult a professional about specific problems