The simplicity is obvious. The press in neutral Spain was not so constrained. The B.1.351 variant first found in South Africa was labeled as Beta, the P.1 variant first discovered in Brazil became Gamma and the B.1.617.2 variant first detected in India is now Delta. The next letters on the list, if it comes to it, which it probably will, are epsilon, zeta, eta and theta. Epsilon refers to the B.1.427 and B.1.429 variants first found in the U.S., Zeta refers to the P.2 variant first discovered in Brazil and Eta refers to the B.1.525 variant initially detected in multiple countries.
Epsilon refers to the P.2 706 and B.1.49 detecting variant in Brazil and Etarpe refers to the B.1.52 and B.1.53.
( z0 and :op ( z1 refer :ARG0 ( z2 spaceship :name ( z3 name :op "Epsilon" ) ) :ARG1 ( z4 and :op ( z5 variant :name ( z6 name :op "P." :op 2 :op 706 ) :ARG1-of ( z7 detect ) ) :op ( z8 variant :name ( z9 name :op "B." :op "1.49" ) :location ( z10 country :name ( z11 name :op "Brazil" ) ) ) ) ) :op ( z12 refer :ARG0 z2 :ARG1 ( z13 and :op z8 ) ) :rel ( z14 name :op "Etarpe" ) :rel 1.53 :rel 1.52 :rel ( z15 B. ) )
(z0 / and
    :op1 (z1 / refer-01
             :ARG0 (z2 / spaceship
                       :name (z3 / name
                                 :op1 "Epsilon"))
             :ARG1 (z4 / and
                       :op1 (z5 / variant
                                :name (z6 / name
                                          :op1 "P."
                                          :op2 2
                                          :op3 706)
                                :ARG1-of (z7 / detect-01))
                       :op2 (z8 / variant
                                :name (z9 / name
                                          :op1 "B."
                                          :op2 "1.49")
                                :location (z10 / country
                                               :name (z11 / name
                                                          :op1 "Brazil")))))
    :op2 (z12 / refer-01
              :ARG0 z2
              :ARG1 (z13 / and
                         :op2 z8))
    :rel (z14 / name
              :op1 "Etarpe")
    :rel 1.53
    :rel 1.52
    :rel (z15 / B.))
Epsilon refers to the P. 2 706 and B. 1.49 detecting variant in Brazil and Etarpe refers to the B. 1.52 and B. 1.53 .
z2 :name z3
z3 :op1 7
z1 :ARG0 z2
z6 :op1 9
z6 :op2 3
z6 :op3 4
z1 :ARG1 z4
z9 :op1 5
z9 :op2 0
z5 :ARG1-of z7
z4 :op1 z5
z5 :name z6
z8 :name z9
z4 :op2 z8
z8 :location z10
z10 :name z11
z11 :op1 6
z0 :op1 z1
z14 :op1 8
z0 :op2 z12
z12 :ARG0 z2
z12 :ARG1 z13
z13 :op2 z8
z0 :rel z14
z0 :rel 2
z0 :rel 1
z0 :rel z15