, Your TM30 record is still valid. As your TM30 receipt has already been submitted, and you have proof of the same address (yellow book) that might be why they didn't ask you for a receipt.
Still, there could be a possibility of being asked for a receipt.
In that case, tell them you don't have a copy, no changes since registering. They just let it go or tell you to get one. If you are directed to get a receipt, go to the TM30 counter for that. As you bring your yellow book, it's not difficult to re-submit or get a receipt there.
-> There is no written limit. However, approval of your entry is always at the discretion of the officer at the passport control desk upon your entry.
If your family will visit you only on holidays, it will not be a problem.
Q. I think I was told by someone you can only visit twice a year on this entry stamp?
-> That is old and incomplete information. There used to be the rule of the limit of two visa-exempt entries by land per calendar year. It has been lifted months ago. There has never been a limit on entries by air.
Your 90-day report online may be rejected, as the online reporting window is now 15 days before until 7 days before the due date.
You have 7 days after the due date to report in person at the local immigration office. You can go tomorrow or a few days later.
Check the status of your report on the system before you go to the local office. Better to cancel if it's still pending when you go, to avoid any confusion.
That’s immigration office-specific. You need to check with your local office for their policy. Some don't require TM30 or proof of address for tourism extension. Some require you to show a TM30 receipt. There are some offices that accept hotel receipts instead of TM30.
I don't recall any report saying a lease agreement was accepted for tourism extension.
, A re-entry permit doesn't have any fixed validity. It has the same expiry date with your current stamp whenever you apply for it.
A re-entry permit is to keep your current stamp (entry or extension) valid when you leave Thailand. It doesn't add any number of days to it.
Re-entry permit would be valid for one day if you apply for it one day before the current stamp validity, for example. Re-entry permit wouldn't be valid longer than the current stamp.
90-day report is to report that you are in Thailand for 90 consecutive days, you are due to report during reporting window if you are in Thailand on the 90th day.
That 7 days after is the "grace period" to report, not for counting days of staying.
You can stay or leave anytime as long as your stamp allows.
Both Australian and British passport holders will be stamped in for 60 days on visa-exempt (not visa waiver) entry now. 60-day Visa-exempt entry is eligible for a 30-day tourist extension one time per entry. You don't need to do anything special to enter Thailand on visa-exempt.
As long as you cancel your extensions properly before you leave Thailand once, usually, you wouldn't have issues entering through northeast land borders. Better to avoid the Poipet/Aranyaprathet border if you want to travel on your own.