When voluntarily freezing coins, all rewards will remain attached to the original coin input that staked the reward, and will remain frozen for either the 1 or 4 month maturity timeframe.
However, if you designate your stake reward to be sent to a separate address that you own, then those rewards will be a mix of both spendable and reserve, based on the whatever the current peg index is.
For example, if you designate your rewards to be sent to a separate address and the peg index is at 0, then you could spend all 40 coins that went to that separate designated address.
If you delegate stake rewards to a separate address and peg is 50% deflated (for example), then about 50% of your 40 coins would be spendable, and the other 50% would be reserve. So it would equate to approximately 20 liquid coins and 20 reserve coins.
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