Rey -
Interesting question so I did some research online and found the following from an article discussing tax effects of mainlanders moving to PR. The author states that your IRA distributions are taxable by U.S. and PR:
Withdrawals from an IRA, 401(k), or other US tax-deferred retirement account would not be covered by Act 22. So moving to the island won’t lessen the tax on withdrawals. The situation is the same with Social Security and other pension income. Puerto Rico has its own IRA system, with both traditional and Roth plans, but it is distinct from the US IRA system. Income from employment in Puerto Rico cannot be
contributed to a US IRA and vice versa.
For a resident of Puerto Rico, a distribution from a US Roth IRA would be taxable by the Puerto Rican government. That is, unless the US Roth IRA is liquidated and the proceeds are used to contribute to a Puerto Rican Roth IRA (subject to contribution limits, which are similar to the US). The opposite is true as well.
A distribution from a US traditional IRA to a Puerto Rico resident would be taxable by both the US and the Puerto Rican government, unless it is liquidated and the proceeds are used to contribute (subject to contribution limits) to a Puerto Rican traditional IRA, in which case the distribution would only be taxable by the Puerto Rican government.
Again, the opposite scenario is true as well. For taxable distributions, the availability of a credit from either government for tax paid to the other prevents double taxation, and you end up effectively only paying the higher rate.