It depends on if the learner is continuing with any of their existing learning aims as part of the new framework or pathway.
See the ILR PSM 12.2.3 Recording transfers for apprenticeship frameworks, Table 9 and following paragraphs.
You record it like a transfer, so you can record a different planned end date if you want, but you don’t have to. As long as it’s got a different start date it’s fine.
Watch out for pathway transfers when they’ve turned 19 since they started. You can still get 16-18 funding as long as they’re still on the same framework, you just have to record EEF as 2. Also, any aims they’re continuing with (perhaps Functional Skills) keep their original dates and can’t be altered, you just switch the pathway. You get component aims that started before the framework they belong to.
The provider support manual has really good guidance on this on page 72.