Reset Values Based on Dropdown

[HangMan]

I have a sheet which shows values by month across several years (sample attached). There are two options in cell A2, 'Alive' and 'Dead'.

I'm trying to find a way, either using a macro or not if it can be done without so that, should the user select 'Dead' from cell A2, that all the values in B2:M2 and O2:Z2 are set to zero. However, I need some way of remembering these values because there may be instances when the user then decides to change Cell A2 back to 'Alive' (and they still need to be able to change the value in any cell at any time) and if they do that, I need the numbers shown in B2:M2 and O2:Z2 to be restored to their last set of values. I assume they somehow need to be stored in an array, but I have no idea how to achieve this in reality.

It should be noted that the same will apply to every row in the sheet of which there will be around 3,000, so this needs to work on a row by row basis and there will be 4 years worth of data, rather than the two on the attached sample.

I'd be extremely grateful for any help as how to achieve this. My VBA is very basic, so if it can be achieved without even better, but if it requires VBA then that is not a problem.

Many thanks