Yes, I modified the weekly calendar template overwrite. However, if I use the default template the problem is still there. It is obvious that there must be this problem if you look at the code in the template:
foreach ($this->days->calendar as $firstDay) {
/* @var $firstDay BookingDay */
$pricesPositions = array();
foreach ($firstDay->boxes as $bkey => $box) {
this will iterate through all the days, and all boxes per day starting from the firstday in the array. However, if the first day in the array doesn't contain the same amount of boxes as all the others, then it will render only the amount of boxes for a specific day. This will break the view of the weekly calendar.
It would be good to build a time grid (from-to) and then render the boxes of each respective day within this time grid.
What do you think?