Yes, the rules vary by province, but there is currently no "official" way to do unlock a LIRA in the App. It's been a feature request for a long time. The unofficial way we currently deal with it, is by allowing the TIME MACHINE to make withdrawals from LIRAs after 65. Essentially it assumes that you have already done some sort of conversion. It still only allows withdrawals up to the maximum amount for a LIF though (that depends on age and province), so it probably won't allow a 50% withdrawal.
For projections it doesn't matter whether the money stays in the LIRA account or put in the RRSP, unless you plan to invest completely differently with different expected returns for those two accounts, or if you plan to make large withdrawals beyond the required minimum withdrawals. Those are uncommon circumstances, so that is why there has not been too much motivation on my part to implement an "official" way. It would bring a lot of complication, as I said the rules vary, it would require additional inputs from users, and if it requires creating an RRSP account that hasn't been entered yet, could also complicate the output. That said, for you or anybody else reading this, you can comment here or on the forum/topic/98-partial-unlocking-of-lira-lif in the feature requests forum and let me know how you would use that feature.