The bug
Recently specifying time in commands got changes to involve <number><s|t|h>
to be able to set the unit of the number. This changed in /time
and the newly added /schedule
but some commands don't have this new syntax yet.
Affected commands
/title timeswai/won't fix/setidletimeoutwai/won't fix/worldborder add|setwai/won't fix/effect give
/weather
WAI/wontfix for /title, /setidletimeout and /worldborder, since they either use client ticks, real world time or unsupported units (like minutes in case of /setidletimeout). Will change /effect give, since it uses world time, even though smallest unit is second.