When should a pachkhan for a saddhaporshi fast been taken?

For Saddhaporshi (Sadh Porsi), the pachkhan is taken before the intended meal time, which is counted from local sunrise. In Jain practice, Sadh Porsi means about 4.5 hours after sunrise; for example, if sunrise is at 6:00 AM, the Sadh Porsi time would be about 10:30 AM. So the vow should be taken in advance of that time, before eating or drinking at that scheduled meal time. ( jainknowledge.com)

If you follow a specific sangh or guru, it is best to follow that local tradition’s guidance on the exact wording and timing. ( jainknowledge.com)