Premiere Pro H.264 export: enforcing a hard maximum bitrate for broadcast ingest

Our delivery spec for a broadcast ingest server caps the absolute peak bitrate of any H.264 file at 12 Mbps, regardless of content complexity. In Premiere Pro's Export Media dialog (Format: H.264), the Bitrate Settings section only exposes a Target Bitrate (Mbps) field plus VBR 1-pass / VBR 2-pass selectors — there is no Maximum Bitrate field and no strict CBR mode.

With VBR, I understand the encoder is free to exceed the target on complex or high-motion frames, so setting the target to 12 Mbps does not guarantee peaks stay under the cap. Lowering the target to leave headroom is a guess, not an enforceable constraint, and re-encoding externally adds a generation loss I'd rather avoid.

Environment: Premiere Pro 2023 (23.x) on Windows, exporting directly via File > Export > Media rather than queueing to Adobe Media Encoder.

1. Is there any supported way — a preset, an advanced export option, or a Media Encoder setting — to impose a true maximum/peak bitrate ceiling on H.264 output from Premiere Pro?

2. If not, does Adobe Media Encoder expose a maximum bitrate control for the same H.264 encoder that Premiere Pro's export dialog hides?

3. Absent a native ceiling, what is the accepted practice for guaranteeing ingest-spec compliance without a full re-encode?