How far ahead should I book it!

I’m a first timer visiting Seattle. If I need to get from a hotel near Seattle Center (Seattle Repertory Theatre) to a restaurant about a mile away near First Ave & Wall St  around 5 pm, how long before 5 pm should I call a taxi or Uber/Lyft?  And if I need to be back at the Seattle Rep by 7:15, again, how far ahead do I need to call? I know from Mapquest the drive will take less than 10 minutes, but I don’t know how long it’s likely to take before my ride arrives.