Oh no, hope everything will be sorted out VERY soon!
We never use the check & send service at the PO. My DH's colleague used it twice (once for passport & once for driving licence I think?!) and both time, the forms came back because there was an error on the form and the person at the PO didn't pick it up. What a waste of money.
Also, someone was meant to sign for the passports etc (we chose secure delivery) but ours was shoved through our letterbox as well. Very secure... not!