Clerics and Druids meming spells question.

[Mordeth]

Quote from SRD

"Each cleric must choose a time at which he must spend an hour each day in quiet contemplation or supplication to regain his daily allotment of spells. Time spent resting has no effect on whether a cleric can prepare spells."

Do you have to choose a time at first level? Can the time ever change? The reason I ask is, that the phb says that any spells cast in the last 8 hours count agaisnt spells prepared the next day. So if jumped in the middle of the night, could I just say that i am preparing spells, a few hours later?

Thanks for the input, as alway

 

[Keith]

You have to choose it at your first Cleric level, I would think.

If your time is, say, dawn, and you are jumped in the middle of the night (so, less than 8 hours before dawn), any spells you cast then will count against your selection for the coming day.

 

[Mordeth]

What if you are underground and dont have access to a watch? Do you have to guess at the time or lose out on preparing for that day?

Could the time you specify be " when i wake up"???