unless you have one with a checkout/until date filled in, a field used by hotels etc. As it will expire on that date, long term stayers should leave it blank so it doesnt expire.
One question would be on the TM30 side, on how old is it? It has to be currently active, that is 'on the new system' (so probably less than 12 months old), and the 'checkout date' mustn't be in the past. (blank is best to prevent expiry).
When i apply yearly for my extension of stay, for which I have a multi-re entry permit, the re entry permit becomes void from the day i submit the application, although it has amonth still to run. If i want to leave the country while my paperwork is considered i have to purchase another Single re entry permit to cover the under consderation period. Then when the extension is approved a new Multi re entry permit with the same dates as the new extension. This obviously leads to overlapping dates on the permits, but only the most recent is recognised.
I'm not sure of the dates, but it has to be getting on for a year since IMM introduced the new TM30 system. Its the new system thats linked, not the old one, and i suspect they have now shut down the old one and not accesable to IMM online process. So you have to have a TM30 on the new system, passport no, address and name have to be same on both sytems, and on the TM30 the 'leaving date' needs to left blank so it doesnt expire and you keep a copy of the pdf so you can use it to fill in the tm47 next time.
maybe i should have said some countries rather than most. It would also depend on circumstances, for a renewal where you have both the old and new passports and not issued via Embassy, i received no letter and wasn't required to produce one at CW when i moved my stamps last time. So if the OP has one then he should produce it when he goes for the swap, but if he wasnt issued with one its probably a waste of time worrying about it.