New TVA rules applying to ongoing AE buying/selling of goods activity

From what I can see online, the doubling of the AE limits did indeed pass the legislature in late December, therefore is law in 2018.

My question concerns how we treat TVA for goods already in stock when or if we pass the TVA threshold in the year. The best way I can describe this is in an example.

I am an auto-entrepreneur buying and selling goods.  Say I import €50,000 of goods on 5th January into France. I am not registered for TVA as I am below the threshold at that time. So therefore I pay €10,000 TVA (20%) to Customs / Impots when the goods arrive at the port of entry in France.

Lets say I sell half of my stock between January and July, and I have gone over the threshold for TVA (so my sales are greater than €91,000). From what I can see online I have to register for TVA for my activity from 1st July onwards (the month in which I have breached the TVA threshold - I also re-invoice everyone already billed in that month to include TVA on their invoices). I can also start offsetting any TVA from valid expense purchases from the month of TVA registration as well (July).

But what about stock purchases (les factures des fournisseurs) ? The remaining half of my stock I will look to sell in the second half of the year, when registered for TVA. I will therefore be charging TVA on these sales.
I will have paid €5,000 purchase TVA on this stock in January of that year.

1 – Can I offset this purchase TVA against the subsequent sales TVA ?

2 – If so, is the offsetting of the TVA only on a sale by sale basis i.e. I can only offset the specific purchase TVA against the specific sales TVA for each individual product once I sell them ?

Apologies if I have explained this in a convoluted way! I tried to look this up yesterday and ended up reading French tax regulations! Still could not find an easy answer. Most explanations explain expense purchases, but I am not sure these are the same as supplier invoices for resellable stock.