If you have an existing claim for CTC that goes from joint to single
because of
separation, you need to tell
them ASAP otherwise they will stop the joint claim, demand repayment and
not start the single claim until the date they were informed (in writing!)
with a possible backdate of 93 days but no more. Reminders about tax
credits only come once a year and it is up to you to know you are supposed
to notify changes within 30 days ... not top of your list when you are in a
state of distress with kids to care for

.
I found this out to my cost

. My ex had always done the CTC paperwork. Despite
years of trying to sort it out - they acknowledge telephoned notification
but would not start single claim for that date and failed to send paperwork
for 12 months .. have ended up abandoning the attempt. Even my MP got
nowhere. Just sent round in circles in the system.
It may also
be that the household income in this case was too great for CTC to be
relevant until Fusca was separated.
I agree though that it was
not the solicitor's responsibility to raise this - although it is odd that
it did not come up when finances were reviewed.
Hadenoughnow