https://www.slab.org.uk/guidance/timely-submission-of-account-of-expenses/
Your account, consisting of your fees and outlays, must be submitted to us no later than four months after the conclusion of the proceedings. This time limit shall begin from the last entry that we consider to be a genuine step in proceedings.
The last entry does not include:
We may accept accounts submitted later than the 4 month limit, if we consider that there is a special reason for this.
Examples of a possible “special reason” are:
We are unlikely to accept forgetfulness, ignorance of the regulations, lack of staff or a law accountant’s delay as special reasons.