I am very stressed with this, thus I kindly ask for any help available.
I am working in Bavaria, Germany. I am seriously considering accepting an offer (should arrive by tomorrow) to work in London in another company. I told them that my notice period is 1 month. When we talked over phone to see what I expect from the offer, I informed them that the apartment I rent has 3 months of "notice period", and they said they'd like to have me onboard ASAP, and we agreed that I would speak to the landlord to see if I can leave earlier - which I did, not happening.
Now they will send me the offer, I will tell them that I have to wait 3 months, they might get a bit unsatisfied. Now, let's say I will accept it by end of October at the latest, which sets the start date at start of February.
The problem is that I have to do my tax declaration here in Germany, and for that I need the Lohnsteuerbescheinigung, which the company sent me early in February 2019 for the year 2018. That document sums up my income and taxes withhold (I have no other income or property, only my job).
So, ideally, if my starting date was March, I would do the tax declaration in early February, wait a couple of weeks to receive the letter in my apartment in Germany, pay whatever tax I would have to pay, and leave the country.
However, I feel a bit afraid of asking to delay my starting date from Feb to March, and that's why I would like you to ask if see a way of my tax declaration happening without asking for a delay (i.e. having my start date in February)?