If it continues to make great beer, no worries. If you have longer lag times, incomplete attenuation, or off flavors, pitch it and start over.
If your "saved" yeast isn't touching the beer, sanitation and temp control are your only real concerns.
Give a man a beer, waste an hour. Teach a man to brew, and waste a lifetime! Bill Owen quote
Why does Happy Hour limit happiness to 1/24 of the day?