@Douglas Young yeah your 25-35 second cold start is totally normal — that 1 second figure is a hot start number, meaning the module already has valid ephemeris, knows its approximate position, and is basically just reacquiring signals it already knows about. Cold start from scratch without any almanac or ephemeris data is going to be 30-60 seconds for most GNSS chips regardless of what the spec sheet headline says, so you're actually in good shape there.
The flash retention question is the right thing to dig into for your use case. Most GNSS chipsets support a backup mode where they write almanac and last-known position to non-volatile memory before shutdown, and then on next power-up they load that data and start a warm acquisition instead of cold. Whether that's exposed depends on the specific chip inside the module — if you can tell me which GNSS IC is on the MultiNav Pro+ I can point you at the right config registers, but typically you're looking for something like a "backup" or "standby" command you send before cutting power, plus a VBACKUP pin that some chips need held at a low voltage to retain SRAM even when main power is off.
For your asset tracker scenario, even a warm start should get you down to 5-15 seconds if the almanac is less than a few hours old, which is a meaningful improvement. If you're seeing power-up intervals measured in hours rather than days, that warm start path might be all you need without having to implement full AGPS.
