Not much you can do, other than wait now. Probably will take another month or so for any claim settlement to be received.
You won't be the only one chasing payment. The school should have sent an email to all parents affected, just advising of the situation.
My experience with Link
MBNA Credit card £10k defaulted 2008.
Ignored all their calls and letters. (Prob hundreds of threat o grams) Never paid them a penny, despite them threatening me with their 'in house fraud dept' .
Guess what, they gave up around 2013, went statute barred in 'early 15, and never heard a peep out of them since.
It was indeed.....the DN expiry date to rectify the breach is the cause of action from when the claimant may enforce.The Judge in this particular ruling stated that if if it was issued later than the last payment or acknowledgment the debtor has enjoyed the benefit of it not appearing on the CRAs for 6/7/8/9 months.......but failed to agree that the creditor had failed to comply with the ICO guidelines in reporting data accurately...goalposts moved or whatever...make of that what you will.