it's to do with the "washup" transaction with C'link

ATO tell c'link what your income was, and hold any return until it is confirmed you don't owe any money to FAO (as returns can be used to pay ftb debts) - the same applies to reco payments from c'link - that result is sent to ATO to make sure you don't owe anything there as FTB supplements and top ups can be used to pay tax debts

the whole wash up process usually only takes a week or so - but it can take up to a month