Saturn

I was successful at getting a "match" for my biz card, opened in June. The offer was 65k/4k/4mo. I requested the increased bonus of 75k soon after this became a thing, about a month later. The response was quick and positive, complete with a reminder to complete MSR by the original date. But the extra 10k posted with the next statement anyway.

So: Yes, and I asked before I completed spend. I believe one should try as soon as the account is online.

For comparison: I had opened my wife's biz a few months earlier, 60k/3k/3mo and asked to be matched to 65k when that - actual - offer went public. Success. However, when I went for a double dip and asked for a second raise to 75k later they denied that citing the fact that they had already added 5k to that account.

Go ahead and SM.

We ought to remember that any match is a gesture of goodwill, and it is very much YMMV. I remember how pissed I was when my first attempt (50k>60k) was nixed. I SM'ed again a few days later and got the Happy to Assist message, along with the extra miles.

I actually do not think the advice about wording is worth much. I have sent SMs with reference to an online ad or an offer on AA.com. They worked. But it's crap shoot, and once they ask you to send in the mailer offer you're out of luck. You could probably try a phone call after that, but obviously the electronic paper trail will make it hard to hide the fact that you have already asked and were denied.

Good luck!