Not sure if this has been considered, but to prevent the site from crashing with the roll out of 1800 PDF backers on the SPC, one way you could release them could be in blocks such as names A-G then wait 3 hours and do names H through N and so on.

We do this at work for some of our updates where we have 40,000 users in the configuration and helps load balance the servers.

However it does take a little more time on our part to ensure no one gets cut out of the division.