Manually caching Rest without checking headers for ETag and Last-Modified

I'm using Rest to make a call to a remote server that I have no access to. I want to cache received data permanently for offline use without checking Last-Modified or ETag in the headers.

I expected CachingMode.MANUAL mechanism to check if there's an offline content and if there's none, then go online to fetch the content, but it doesn't.

To circumvent this, I had to first use Rest with CachingMode.OFFLINE and if that returns 404, then make another call with CachingMode.SMART.

Shouldn't there be an option of (let's say CachingMode.OFFLINE_FIRST) that checks offline first and if no content then goes online with (CachingMode.SMART)?

Below is my current approach:

Response<Map> response = Rest.get(url)
        .cacheMode(CachingMode.OFFLINE)
        .queryParam("param", value)
        .jsonContent().onErrorCodeJSON(e -> {
            throw new RuntimeException(createErrorMessage(e));
        }).onError(e -> {
            if (e.getResponseCode() == 0 || e.getConnectionRequest().getResponseCode() == 404) {
                is404 = true;
                return;
            }

            throw new RuntimeException("Network error. Please check your connection and try again.");
        }).timeout(6000).getAsJsonMap();

if (is404) {
    is404 = false;
    response = Rest.get(url)
            .cacheMode(CachingMode.SMART)
            .queryParam("param", value)
            .jsonContent().onErrorCodeJSON(e -> {
                throw new RuntimeException(createErrorMessage(e));
            }).onError(e -> {
                throw new RuntimeException("Network error. Please check your connection and try again.");
            }).timeout(6000).getAsJsonMap();
}