In the case you were eligible before leaving Germany, you can still get ALG1 if you do the timing right. You are eligible if you contributed at least 12 months in the past 30 months. Thus, you can still receive benefits if you apply less than 18 months after your departure. Example: you stay in Bacerlona 15 months after your time in Germany. You come back to Germany, this time frame rule won't let you have ALG1 (15 months in the UK + 9 months in Germany before that = 24 months)