Because that's what I said?... I don't understand what you're asking why about.

Wow, you took the plunge. What was the tipping point of your decision to finally go all the way?

Make a police report on the missing IC just in case some one use it illegally. make a copy of police report and keep it with you.

I never show my ic when crossing custom.  Only those long term pass or permit holder need to show their ID at SG custom.

Double check the re-entry permit expired date. You should have a print out that you fold nicely and keep it with your passport.

It remind me once I saw a couple accidentally cross SG custom with expired re entry permit during CNY. The officer was kind enough to bring the couple to office and warn them of the risk of voiding Their PR. They make a U turn with the rest of family members and barang barring.