I lately had a cooperative shut of a Lightning channel and the 2 nodes agreed a payment fee of about 1 sat/vbyte for the closing transaction. (This was positive by me; I all the time prefer to hold charges low and was/am in no rush.) The transaction was evicted from the mempool a couple of hours later due to the latest excessive quantity.

The transaction subsequently reappeared within the mempool. That is good, however how did it get there? I am unable to see something apparent in my node’s logs about observing the transaction to have been evicted, resubmitting it or noticing that the peer had resubmitted it, however possibly I simply do not know what to search for.

Is the behaviour on this state of affairs standardised? If not, how do the totally different Lightning implementations (significantly lnd and Core Lightning) behave?

Out of paranoia I manually saved a replica of the transaction so I may resubmit it if it obtained utterly misplaced; was there any want for me to do this?