I am struggling to understand the grammar in this sentence. My thought is that it is the future perfect tense: (conjugated werden + past participle + haben or sein), but this sentence doesn't contain the 'haben or sein' element, and the 'werden' is at the end.
Is this somehow due to modal auxiliary verb, müssen? But having looked it up, the future tense looks something like (conjugated werden + infinitive modal).
Any help on what grammar is being used in this sentence will be much appreciated.