I am not exactly sure what you want - but I think this is close.
1. Creating a timer that blocks the MATLAB command line for a certain time.
%% Create a timer
t = timer('Name','maxtimeBetweenEvents','StartDelay',30,'TimerFcn',@(x,y)disp('Hello World!'),'Tag','Waiting');
%% Start a timer
start(t)
%% Start your waiting
wait(t)
disp('The wait is over!')
2. To restart the timer.
start(t)
wait(t)
disp('The wait is over!')