Climbing Rose Conundrum: how long to keep in original pot?

Hi Rosarians! I impulse bought a DA Generous Gardener (SO EXCITED!) about a week ago, and, upon more level-headed reflection, the spot that would make the most sense to plant this rose into might not be ready for a few months. Whoops.

Any opinions about how long I can keep it in its original pot without stressing it too much? Or, if I do need to plant it into a temporary home, would I be better served to pop it in the ground, or plant it into a makeshift container (IE a rubbermaid tote with drain holes)?