Hidden tabs showing for other users in shared file

I have a shared file saved on our network.  It has many tabs, one for each week of the year, for a large remote team to enter data on weekly.  There are then summary tabs to analyse the data.  I have hidden most of the tabs, with currently only the January and February weeks showing, to make it easier to use / less scrolling through tabs.  However, some users when they open the file, cannot see the same tabs as me - for example, the February ones are missing.  They are able to Unhide them themselves, but why would the view be different for different users?  Is there a setting on their laptops which means it doesn't show the same?  When they enter data and save the file, the data shows when I open it, so they are using the correct file and it works.  It is a Shared File so multiple users can enter data at the same time, and I have not used the new co-authoring feature, just the legacy Shared Workbook feature.  I do not want to protect the file or lock it down, I just want it to show them the relevant tabs when they open it.  Does anyone have any ideas?  Thanks in advance.