Repository: yt-dlp
Issue: --mtime broken when downloading fragments with aria2c
Labels: bug,core:downloader

### Checklist

- [X] I'm reporting a bug unrelated to a specific site
- [X] I've verified that I'm running yt-dlp version **2022.03.08.1**. ([update instructions](https://github.com/yt-dlp/yt-dlp#update))
- [X] I've checked that all provided URLs are alive and playable in a browser
- [X] I've checked that all URLs and arguments with special characters are [properly quoted or escaped](https://github.com/ytdl-org/youtube-dl#video-url-contains-an-ampersand-and-im-getting-some-strange-output-1-2839-or-v-is-not-recognized-as-an-internal-or-external-command)
- [X] I've searched the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues including closed ones. DO NOT post duplicates
- [x] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)

### Description

aria2 version: 1.36.0

While not using aria2c as external-downloader, the date modified is correct since default is `-mtime`
However, the date modified is not correct even add `-mtime` manually and set `remote-time=true` in aria2.conf
![d](https://user-images.githubusercontent.com/68129013/160291162-dc90f12f-487b-4525-93e0-da55d13796d6.jpg)
![a](https://user-images.githubusercontent.com/68129013/160291164-900ce7b1-d9ed-4a3c-ae2d-e88a255b27e6.jpg)

Here is the codes for testing your own

```
yt-dlp -vU --output "default.%(ext)s" -- "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4"
```
```
yt-dlp -vU --external-downloader aria2c --output "aria.%(ext)s" -- "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4"
```

Don't know is this affect the date?
![a_frag](https://user-images.githubusercontent.com/68129013/160292172-5e8f77d4-0a02-4046-947f-381a8c9c4c77.png)

frags have different date and yt-dlp take the last frag's date as final output date?


### Verbose log

```shell
yt-dlp -vU --output "default.%(ext)s" -- "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4"
[debug] Command-line config: ['-vU', '--output', 'default.%(ext)s', '--', 'https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4']
[debug] Encodings: locale cp1252, fs utf-8, out utf-8, err utf-8, pref cp1252
[debug] yt-dlp version 2022.03.08.1 [c0c2c57] (win_exe)
[debug] Python version 3.8.10 (CPython 64bit) - Windows-10-10.0.19043-SP0
[debug] exe versions: ffmpeg 2022-03-24-git-28d011516b-full_build-www.gyan.dev (setts), ffprobe 2022-03-24-git-28d011516b-full_build-www.gyan.dev
[debug] Optional libraries: brotli, Cryptodome, mutagen, sqlite, websockets
[debug] Proxy map: {}
Latest version: 2022.03.08.1, Current version: 2022.03.08.1
yt-dlp is up to date (2022.03.08.1)
[debug] [generic] Extracting URL: https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4
[generic] J2mE3uWZjL6wvRQe: Requesting header
[debug] Identified a direct video link
[generic] J2mE3uWZjL6wvRQe: Downloading m3u8 information
[debug] Formats sorted by: hasvid, ie_pref, lang, quality, res, fps, hdr:12(7), vcodec:vp9.2(10), acodec, filesize, fs_approx, tbr, vbr, abr, asr, proto, vext, aext, hasaud, source, id
[debug] Default format spec: bestvideo*+bestaudio/best
[info] J2mE3uWZjL6wvRQe: Downloading 1 format(s): 1280
[debug] Invoking downloader on "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/720x720/THNaWd8y8qmQpR4g.m3u8?container=fmp4"
[hlsnative] Downloading m3u8 manifest
[hlsnative] Total fragments: 5
[download] Destination: default.mp4
[download] 100% of 383.86KiB in 00:00
[debug] ffprobe command line: ffprobe -hide_banner -show_format -show_streams -print_format json "file:default.mp4"

yt-dlp -vU --external-downloader aria2c --output "aria.%(ext)s" -- "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4"
[debug] Command-line config: ['-vU', '--external-downloader', 'aria2c', '--output', 'aria.%(ext)s', '--', 'https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4']
[debug] Encodings: locale cp1252, fs utf-8, out utf-8, err utf-8, pref cp1252
[debug] yt-dlp version 2022.03.08.1 [c0c2c57] (win_exe)
[debug] Python version 3.8.10 (CPython 64bit) - Windows-10-10.0.19043-SP0
[debug] exe versions: ffmpeg 2022-03-24-git-28d011516b-full_build-www.gyan.dev (setts), ffprobe 2022-03-24-git-28d011516b-full_build-www.gyan.dev
[debug] Optional libraries: brotli, Cryptodome, mutagen, sqlite, websockets
[debug] Proxy map: {}
Latest version: 2022.03.08.1, Current version: 2022.03.08.1
yt-dlp is up to date (2022.03.08.1)
[debug] [generic] Extracting URL: https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/J2mE3uWZjL6wvRQe.m3u8?tag=12&container=fmp4
[generic] J2mE3uWZjL6wvRQe: Requesting header
[debug] Identified a direct video link
[generic] J2mE3uWZjL6wvRQe: Downloading m3u8 information
[debug] Formats sorted by: hasvid, ie_pref, lang, quality, res, fps, hdr:12(7), vcodec:vp9.2(10), acodec, filesize, fs_approx, tbr, vbr, abr, asr, proto, vext, aext, hasaud, source, id
[debug] Default format spec: bestvideo*+bestaudio/best
[info] J2mE3uWZjL6wvRQe: Downloading 1 format(s): 1280
[debug] Invoking downloader on "https://video.twimg.com/ext_tw_video/1506297848199094272/pu/pl/720x720/THNaWd8y8qmQpR4g.m3u8?container=fmp4"
[hlsnative] Downloading m3u8 manifest
[hlsnative] Fragment downloads will be delegated to aria2c
[hlsnative] Total fragments: 5
[download] Destination: aria.mp4
[debug] aria2c command line: aria2c -c "--console-log-level=warn" "--summary-interval=0" "--download-result=hide" "--http-accept-gzip=true" "--file-allocation=none" -x16 -j16 -s16 "--allow-overwrite=true" "--allow-piece-length-change=true" --header "User-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36" --header "Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8" --header "Accept-encoding: gzip, deflate, br" --header "Accept-language: en-us,en;q=0.5" --header "Sec-fetch-mode: navigate" "--check-certificate=true" "--remote-time=true" "--show-console-readout=true" "--auto-file-renaming=false" "--file-allocation=none" "--uri-selector=inorder" -i aria.mp4.part.frag.urls
[aria2c] Downloaded 393071 bytesDL:139KiB]
[download] 100% of 383.86KiB in 00:01
[debug] ffprobe command line: ffprobe -hide_banner -show_format -show_streams -print_format json "file:aria.mp4"
```