"it'll be all right on the night" meaning in English

{
  "etymology_text": "Originally said about the problems encountered during the final dress rehearsal before the premiere (first night) of a performance.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase"
      },
      "expansion": "it'll be all right on the night",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with language name categories using raw markup",
          "parents": [
            "Entries with language name categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Although it seems problematic now, it will ultimately succeed."
      ],
      "id": "en-it'll_be_all_right_on_the_night-en-phrase-RSHEbdoN",
      "raw_glosses": [
        "(UK, informal) Although it seems problematic now, it will ultimately succeed."
      ],
      "tags": [
        "UK",
        "informal"
      ]
    }
  ],
  "word": "it'll be all right on the night"
}

{
  "etymology_text": "Originally said about the problems encountered during the final dress rehearsal before the premiere (first night) of a performance.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase"
      },
      "expansion": "it'll be all right on the night",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        "British English",
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English phrases",
        "English rhyming phrases",
        "English terms with non-redundant non-automated sortkeys"
      ],
      "glosses": [
        "Although it seems problematic now, it will ultimately succeed."
      ],
      "raw_glosses": [
        "(UK, informal) Although it seems problematic now, it will ultimately succeed."
      ],
      "tags": [
        "UK",
        "informal"
      ]
    }
  ],
  "word": "it'll be all right on the night"
}