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My PR 13600 works as expected.
I simplified attached continue.py: see attached traceme.py.
Output with optimizations
---
$ ./python traceme.py 
 6 0 LOAD_CONST 1 (0)
 2 STORE_FAST 0 (a)
 7 4 LOAD_GLOBAL 0 (range)
 6 LOAD_CONST 2 (3)
 8 LOAD_CONST 3 (4)
 10 CALL_FUNCTION 2
 12 GET_ITER
 >> 14 FOR_ITER 30 (to 46)
 16 STORE_FAST 1 (n)
 8 18 LOAD_FAST 1 (n)
 20 LOAD_CONST 4 (2)
 22 BINARY_MODULO
 24 POP_JUMP_IF_FALSE 14
 9 26 LOAD_FAST 1 (n)
 28 LOAD_CONST 2 (3)
 30 BINARY_MODULO
 32 POP_JUMP_IF_FALSE 14
 10 34 LOAD_FAST 0 (a)
 36 LOAD_CONST 5 (1)
 38 INPLACE_ADD
 40 STORE_FAST 0 (a)
 11 42 JUMP_ABSOLUTE 14
 44 JUMP_ABSOLUTE 14
 >> 46 LOAD_CONST 0 (None)
 48 RETURN_VALUE
 --- modulename: traceme, funcname: func
traceme.py(6): a = 0
traceme.py(7): for n in range(3, 4):
traceme.py(8): if n % 2:
traceme.py(9): if n % 3:
traceme.py(7): for n in range(3, 4):
---
Output without optimizations (-X noopt):
---
$ ./python -X noopt traceme.py 
 6 0 LOAD_CONST 1 (0)
 2 STORE_FAST 0 (a)
 7 4 LOAD_GLOBAL 0 (range)
 6 LOAD_CONST 2 (3)
 8 LOAD_CONST 3 (4)
 10 CALL_FUNCTION 2
 12 GET_ITER
 >> 14 FOR_ITER 30 (to 46)
 16 STORE_FAST 1 (n)
 8 18 LOAD_FAST 1 (n)
 20 LOAD_CONST 4 (2)
 22 BINARY_MODULO
 24 POP_JUMP_IF_FALSE 44
 9 26 LOAD_FAST 1 (n)
 28 LOAD_CONST 2 (3)
 30 BINARY_MODULO
 32 POP_JUMP_IF_FALSE 42
 10 34 LOAD_FAST 0 (a)
 36 LOAD_CONST 5 (1)
 38 INPLACE_ADD
 40 STORE_FAST 0 (a)
 11 >> 42 JUMP_ABSOLUTE 14
 >> 44 JUMP_ABSOLUTE 14
 >> 46 LOAD_CONST 0 (None)
 48 RETURN_VALUE
 --- modulename: traceme, funcname: func
traceme.py(6): a = 0
traceme.py(7): for n in range(3, 4):
traceme.py(8): if n % 2:
traceme.py(9): if n % 3:
traceme.py(11): continue
traceme.py(7): for n in range(3, 4):
---
The difference on the trace is that using -X noopt, "traceme.py(11): continue" line is traced as expected.
The difference on the bytecode is that jumps are no longer optimized using -X noopt:
* Optimized:
 "32 POP_JUMP_IF_FALSE 14"
* Not optimized:
 "32 POP_JUMP_IF_FALSE 42"
 ">> 42 JUMP_ABSOLUTE 14"
The peephole optimizer replaces a jump to an unconditional jump with a jump directly to the target of the unconditional jump.
I documented peephole optimizations in my reimplementation in pure Python:
https://bytecode.readthedocs.io/en/latest/peephole.html#optimizations
(I'm not sure that it's up to date, but it should give you an idea of which kinds of optimizations are implemented.)