"..... the next 2 ingredients are added, the strong tea (you may notice from the first piccy - I just showed the box - nice strong caterers tea from Preston. Not any of that namby pamby Yorkshire piddle

).
No seriously, any normal "black tea" should do - for those overseas something named "english breakfast tea" or similar should do the job - I suspect that the original author of the recipe was thinking of Indian tea, though something like "Orange Pekoe" (which I think is Chinese black tea) or maybe Oolong etc etc would do the job.<br />
Please remember that some of the more "famous "teas are actually "flavoured"; e.g. Earl Grey has bergamot, which would probably be detectable in the finished mead - so it's up to you and what you may be trying to achieve."