I have a list of sequences (12527). On this, I perform MAFFT to get the sequence alignment in clustal format. FastTree is used to generate the phylogenetic tree from the clustal format file.

Currently, if I encounter a new sequence then the entire procedure is done again to generate the new phylo tree. Is there a method where this procedure can be bypassed partially or fully (by leveraging the previous files i.e sequence aligned file and tree file) to generate the tree.