Severe acute respiratory syndrome coronavirus 2 Wuhan-Hu-1, complete genome

Once one is there, it's easy to see that there are also many other sequencings in the database, isolated on different locations. E.g.

https://www.ncbi.nlm.nih.gov/nuccore/MT370930

"collection_date="2020-03-22""

"Submitted (22-APR-2020) Center for Research on Influenza Pathogenesis (CRIP), New York, NY 10029-6574, USA"

One question (If someone please can explain me) : if coronavirus is an RNA virus, why in the genome at end we can see "t" (timina, I don't know the name in english sorry!) and not "u" (uracile)?

https://bioinformatics.stackexchange.com/questions/11353/why...

"Virtually all sequencing of RNA viruses is done through cDNA"

Could someone post some helpful references on how the data is structured?

Going off the links at the top, it's Genbank[1] or FASTA[2] (although the stuff on the FASTA version doesn't really match the example on the FASTA explanation.)

[1] http://scikit-bio.org/docs/0.5.2/generated/skbio.io.format.g...

[2] https://zhanglab.ccmb.med.umich.edu/FASTA/