Stannis's Northern Cavalry reads:
Stannis's Northern Cavalry cannot be killed or discarded from play during a phase in which its STR has been raised or lowered.
King's Pavillion reads:
Each character gets +3 STR while it is standing.
Does this mean that Stannis's Northern Cavalry cannot be killed in any phase that it was standing while King's Pavillion is in play, or because it is a static effect is the Cav only same the phase the pavillion comes into play and the phase the Cav kneels?
Thanks for your help in advance.

