Interactive Brokers partitions and PDT

[Adam Lewis 64]

I use IB for long term ETF investments. I am approaching $25,000 invested in these ETFs, and so can soon also begin to use the account for day trading above the PDT rule (I currently use CMEG but the lack of shares for short is restrictive, hence I'd like to move as soon as possible). I'm aware it's possible to partition IB accounts. Ideally once over $25,000 I'd create two partitions - one for investing to keep my ETFs and one for trading that I can fund and use separately. However I'm not sure if each partition would need to be over $25,000 to satisfy PDT, or whether the total value of the account and all partitions within is what's taken into account? I've got a call out to IB customer services but they're taking a long time to reply, and I wonder if anyone here has an idea. Thanks!