Over-paying FIT to Get Series I Bonds?

Anyone see any problems with the strategy of overpaying 2022 estimated FIT to get the extra $5K in I Bonds?

No problem at all. I did it for 2021, and they mailed me the I-Bonds very quickly (for them) after I filed, I’m thinking a week or two. My only error was that I underestimated my taxes due slightly, thus I ended $100 below the maximum of the $5,000 maximum this way. One can then go through the process of having the paper bonds converted to electronic. In addition to this, of course, you can buy I-bonds up to $10,000 “per Social Security Number of the first person named as owner of a bond or, for an entity, per Employer Identification Number.”