[Seerah]

There are two even better ways to accomplish this that do not use any sort of a timer to poll to see if it's ready.

#1 - Have the script you assign to the zo_callLater call actually call the next function when it's finished.

local function callAnotherSubFunction()
     --do other stuff after zo_callLater is finished
end
 
local function callFirstSubFunction()
     --do stuff
     zo_callLater(100, function()
               --do something later
               callAnotherSubFunction()
          end)
end
 
local function mainFunction()
    callFirstSubFunction()
end

#2 - Use callbacks. Register for a custom callback (a custom event) which is fired by the zo_callLater call, and have your callback handler be the second function.

local function callFirstSubFunction()
     --do stuff
     zo_callLater(100, function()
               --do something later
               CALLBACK_MANAGER:FireCallback("zo_callLaterFinished")
          end)
end
 
local function callAnotherSubFunction()
     --do other stuff after zo_callLater is finished
end
 
local function mainFunction()
    callFirstSubFunction()
end
 
CALLBACK_MANAGER:RegisterCallback("zo_callLaterFinished", callAnotherSubFunction)